Fluorescent tube lampholder with compact switching means operable with the insertionand removal of a fluorescent lamp



p 1968 E. J. M LAUGHLIN 3, 01,242

FLUORESCENT TUBE LAMPHOLDER WITH COMPACT SWITCHING MEANS OPERABLE WITH THE INSERTION AND REMOVAL OF A FLUORESCENT LAMP Original Filed April 29, 1966 WITNESSES INVENTOR We fQ/ Emmefi J. MC Loughli 5 W ATTORNEY United States Patent C FLUORESCENT TUBE LAMPHOLDER WITH COM- PACT SWITCHING MEANS OPERABLE WITH THE INSERTION AND REMOVAL OF A FLUO- RESCENT LAMP Emmett J. McLaughlin, Fairtield, Conn., assignor to Westinghouse Electric Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Continuation of application Ser. No. 546,244, Apr. 29, 1966. This application Oct. 11, 1967, Ser. No. 674,679

3 Claims. (Cl. 200--51.07)

This application is a continuation of Ser. No. 546,244, filed Apr. 29, 1966, now abandoned.

The present invention relates generally to fluorescent type lampholders and particularly to a unique and simple switching means disposed within an insulating housing of a lampholder.

In certain fluorescent light applications and fixture installations, such as with light dimming means, it is often required that the ballast primary circuit be open when the fluorescent lamp is removed from the lampholders. This is required as a safety precaution if the output potential of the ballast is more than 300 volts.

The simplest and most reliable and economical switch or circuit interrupting means should ordinarily operate with the simple insertion and removal of the lamp in and out of the lampholder. In order to insure and enhance simplicity and economy to both the manufacturer and consumer, the switching or interrupting means should include or 'at least work compatibly with integral quickwiring terminal means that eliminate costly wire connecting means such as wire nuts and time consuming splicing operations. Further, the lampholding base or housing should be economical to manufacture, easy to mount on the light fixture, and simple to use by the user.

The present disclosure describes such means embodying principles based upon the criteria outlined above. Briefly, the present invention comprises a compart, molded plastic base or housing axially supporting two integral spring grip brush terminals designed to grip lamp pins adjacent one end and connecting wire leads at the other end. The end of the molded housing adjacent the wire connecting end of the brush terminals has a lateral portion or platform extending in a direction generally normal thereto with the lateral portion having apertures therein for receiving the connecting wires and a securing means (such as a bolt or rivet) to fasten the lampholder to a fixture b'ase. One of the brush terminals is a full spring grip structure having a dual end that functions as two spring wedges against a wall surface of the plastic base when two wire leads are inserted therebetween. The other terminal means is partially cut-away adjacent its wire gripping end so that it has only a single end for gripping one inserted wire. A special spring contact and insulating divider is disposed in the cut-away area of the terminal so that one end of the special spring contact forms the second wire gripping end while its other end is disposed in close proximity to 'a wide portion of the terminal means for contact therewith when the pins of a fluorescent lamp inserted into the lampholder force the wide terminal portion against the special contact end. The insulating divider rests between the cut-away terminal and the special contact to maintain their electrical separation while the lamp is out of the holders and the terminals remain unfiexed.

It is therefore an object of the present invention to provide a novel, compact, low cost lampholder having means capable of switching a circuit with the removal or replacement of a lamp.

Another object of the invention is to provide a unique circuit interrupting lampholder with quick-wiring terminal means for connecting lead wires.

A further object of the invention is to provide a lampholder with low cost yet reliable components, and rapid assembly and expedient user features.

A more specific object of the invention is to provide a novel lampholding device containing a simple, reliable and economical circuit interrupting means that functions compatibly with quick-wiring terminals forming an integral part of brush terminals for receiving fluorescent lamp pins.

These and other objects of the invention will become more apparent from the following detailed description taken in connection with the accompanying drawing, in which:

FIGURE 1 is an exploded isometric view of a lampholder constructed in accordance with the principles of the invention;

FIG. 2 is a front elevation view of the lampholder of FIG. 1 with all components except the cover in place;

FIG. 3 is an end view of the lampholder taken along lines III-III of FIG. 2; and

FIG. 4 is a view of the lampholder terminals flexed in phantom outline.

Specifically, a preferred embodiment of the invention is shown in FIG. 1 in which the separate components that form novel lampholder 10 are shown in perspective. Lampholder 10 comprises a small insulating open face housing 12 having side walls 11, a rear face wall 13 and an integral lateral extension or platform 14 at one end thereof for mounting the lampholder on a lighting fixture (not shown). Lampholder 10 may be secured to the fixture by a bolt or similar means (not shown) extending through opening 16 in platform 14. Device 10 may further be secured to a fixture by simply inserting housing 12 into a cut-out portion provided in the fixture (not shown) so that the fixture extends into slots 18 provided in the lower side portions of housing 12. With the fixture extending into slots 18 and therefore partially enveloping base 12 in the plane of the slots, the fixture and housing 12 are held together during the assembly process thereof without further securing steps being necessary.

Directly underneath opening 16 in platform 14 is a substantially square and partially enclosed area formed by ridges 15 which serves the purpose of receiving a nut and preventing it from turning when a bolt is used in opening 16 to secure lampholder 10 to a fixture surface.

As best seen in FIG. 2, lamp energizing brush terminal means 30 and 31 rest in housing 12 in a manner to receive the pins of a fluorescent lamp (not shown) through an opening 26 in the end of the housing. After the lamp is inserted, it is turned in the well known manner until the pins (not shown) travel around bosses 24 and seat in indent portions 32 provided adjacent one end of the terminal means 30 and 31. Wire engagement arms 34 and 35 are provided at the other end of terminal means 30 and 31 respectively as an integral part thereof. The terminal means are further formed to fit in and around housing bosses 27 and 28 (see FIG. 2) so as to be adequately spring biased with the lamp pins or connecting wires in place.

The end edges of wire engagement arms 34 and 35 face toward ledge portions 22 formed as a part of the sidewalls 11 of housing 12 and together therewith form the wire gripping means that secure bared wire ends inserted therebetween. The ends of the bared wire leads are inserted through openings 20 provided in platform 14 immediately beneath and in alignment with the end edge portion of engagement arms 34 and 35 as best seen in FIGS. 2

and 3. Engagement arms 34 and 35 provide simple, quickwiring means that enables the manufacturer or user of lampholder to Wire the device with little effort. Openings enhance the simplicity of the wiring and connecting function by making the gripping edges of arms 34 and readily available and accessible. And the connecting Wires can be readily released by simply inserting a flat object, such as a small screwdriver, into opening 20 and forcing arms 34 or 35 up and away from ridge surface 22. The arms are further provided with axially extending groove portions 37 (FIG. 1) that accommodate the wire ends as they are inserted thereagainst and assist in directing the wires into the space between the gripping ends of the arms and wall surface 22. Preferably, the gripping edges of arms 34 and 35 are further provided with a notched surface 36 (FIG. 3) to produce added wire engagement area that gives added assurance of positive wire engagement and retention.

Terminal means 31, on the left as seen in FIG. 1, is provided with a cut-out portion 33 that eliminates one engagement arm leaving terminal means 31 with only one integral Wire engaging arm 35 in contrast to the two (dual) engagement arms 35 integral with left-hand terminal means 30. Cut-out portion 33 is dimensioned to receive and hold an insulating spacer which fits in the cut-out and over the terminal when it is disposed in place in housing 12. Spacer 40 is generally laterally dimensioned to rest in the space provided between center ridge 21 and the opposite side wall surface 22 (see FIG. 2) with a hole 44 designed to accommodate a protruding post 23 provided in housing 12 that assists in securing the spacer 40 in place. The spacer is further provided with a tab portion 42 that extends into the right-hand opening 20 in platform 14 which serves to further hold spacer 40 in place.

Over spacer 40 is disposed a separate and special spring grip contact designed to make electrical contact with terminal means 31 when the pins of a lamp are inserted in housing 12 and turned to seat in indents 32 of the terminal means. Contact 50 is disposed against insulating spacer 40 with its switching end extending to a point in close proximity to the wide portion of terminal means 31. As shown in FIG. 4, the unfleXed terminal 31 does not make physical contact with special contact 50, but with terminal 31 flexed, such as when lamp pins are inserted thereagainst, the wide portion of the terminal above cutout 33 is forced against the upper edge of contact 50 so as to make physical and electrical contact therewith. Insulating spacer 40 maintains terminal 31 and contact 50 electrically separated when the lamp is out of its holder 12 and terminal 31 is unflexed. Thus, terminal and contact means 31 and 50 provide a very simple yet effective switching means within housing 12 for completing or interrupting a circuit provided by connecting leads (not shown) secured in electrical contact with Wire engaging arm 35 and a similar arm 52 respectively forming part of the special contact 50. For example, a primary ballast circuit may include contact means 31 and 50. Bared ends of leads from the ballast can be simply inserted through opening 20 in platform 14 marked DISC for the disconnect side (see FIG. 3) and into the wire gripping; space between the ends of arms 35, 52 and wall surface 22. By such means, the ballast circuit is simply yet reliably connected and ready for operation with the insertion of lamp pins between insulating bosses 24 and brush terminal indents 32.

The engaging arm 52 of contact 50 has a configuration substantially like that of wire engaging arm 35 so that the engagement arm 52 lies in the lateral plane of arm 35 with arm 52 having the same general structural characteristics described above in connection with arms 34 and 35, see FIGS. 2 and 3.

With spacer 40 and terminal means 30, 31 and 50 as sembled in place, insulating cover means is disposed in place thereover to secure the components in ho suing 12. Cover60 is easily disposed in place by first directing its two top corners 62 under two lip or ledge portions 25 molded in housing 12 and then simply pressing cover 60 against the housing until cover projections 64 snap into wire, lead openings 20. The cover is held securely by an interference fit thus eliminating the need for fasteners such as screws, rivets and the like. To enhance the ease and simplicity of assembling cover 60 and housing 12,

cover 60 can be made of a resilient substance, suchas a thermoplastic material, which will flex when the disposing force is applied and return to its original shape after the force is released when the cover is in place.

In viewing the end of lampholder 10 in FIG. 3, the accessibility of wire engagement terminals 34, 35 and 52 is clearly seenpSwitching terminals 35 and 52 are clearly marked DISC so that the user will instantly know their location. Thus the present invention provides an efficient and effective switching means that utilizes the inherent ad vantages of quick-wiring terminal means and a housing structure that allows clear and direct viewing of the terminal means for ease of wire lead connecting and disconnecting. The structure disclosed further provides a reliable lamp switching means that is compact, simple and economical to manufacture, assemble and use.

Though the invention has been described with a certain degree of particularity, it is to be understood that the disclosure has been made by way of example only and that changes may be made therein without departing from the spirit and scope of the invention.

I claim:

1. A lampholder comprising:

a housing made of insulating material having a base at one end, one face wall and side walls extending from the base along the outer edges of the face wall in converging relation to form a tapered, thin housing structure, the face opposite said face wall being open,

spaced opposed terminal strips of resilient electrical conducting material in said housing extending generally from end to end thereof adjacent said side Walls respectively, said terminal strips being shaped to have supported portions which are close together adjacent said base but having their adjacent ends extending outwardly in opposite directions to form short flexible wire engaging portions,

the other ends of said terminal strips having flexible lamp terminal pin engaging portions adjacent their outer ends,

means in said housing engaging opposite sides of said terminal strips at their supported portions to support these portions against flexing but permitting flexure of said flexible portions,

one of said terminal strips having one of its wire engaging portions cut away,

a contact strip of conducting material having one end received within the cut away portion of said one terminal strip in coplanar relation to form a pair of narrow flexible wire engaging portions,

the other end of said contact strip diverging from said one terminal strip to a point close to but normally spaced from the outer side of the uncut portion of said one terminal strip, and

means in said housing for substantially rigidly supporting said other end of said contact strip so that the uncut portion of said one terminal strip will engage said other end of said contact strip when the pins of a lamp are inserted against the lamp pin engaging portions of said terminal strips.

2. The lampholder of claim 1 in which an insulating spacer is disposed between the wire engaging portions of the one terminal strip and the contact strip.

5 6 housing structure to form a second face wall covering 3,060,480 10/1962 Pistey 33953 the open face of the housing structure. 3,138,418 6/1964 Dazley et a1. 33950 3,206,710 9/1965 McLaughlin. References Cited UNITED STATES PATENTS 5 ROBERT K. SCI-IAEFER, Primary Examiner.

2,284,367 5/1942 Bryant et a1 339 s3 X i mnrExamine1-. 2,767,349 10/1956 Feinberg 20051.09X 

1. A LAMPHOLDER COMPRISING: A HOUSING MADE OF INSULATING MATERIAL HAVING A BASE AT ONE END, ONE FACE WALL AND SIDE WALLS EXTENDING FROM THE BASE ALONG THE OUTER EDGES OF THE FACE WALL IN CONVERGING RELATION TO FORM A TAPERED, THIN HOUSING STRUCTURE, THE FACE OPPOSITE SAID FACE WALL BEING OPEN, SPACED OPPOSED TERMINAL STRIPS OF RESILIENT ELECTRICAL CONDUCTING MATERIAL IN SAID HOUSING EXTENDING GENERALLY FROM END TO END THEREOF ADJACENT SAID SIDE WALLS RESPECTIVELY, SAID TERMINAL STRIPS BEING SHAPED TO HAVE SUPPORTED PORTIONS WHICH ARE CLOSE TOGETHER ADJACENT SAID BASE BUT HAVING THEIR ADJACENT ENDS EXTENDING OUTWARDLY IN OPPOSITE DIRECTIONS TO FORM SHORT FLEXIBLE WIRE ENGAGING PORTIONS, THE OTHER ENDS OF SAID TERMINAL STRIPS HAVING FLEXIBLE LAMP TERMINAL PIN ENGAGING PORTIONS ADJACENT THEIR OUTER ENDS, MEANS IN SAID HOUSING ENGAGING OPPOSITE SIDES OF SAID TERMINAL STRIPS AT THEIR SUPPORTED PORTIONS TO SUPPORT THESE PORTIONS AGAINST FLEXING BUT PERMITTING FLEXURE OF SAID FLEXIBLE PORTIONS, ONE OF SAID TERMINAL STRIPS HAVING ONE OF ITS WIRE ENGAGING PORTIONS CUT AWAY, 